<template>
  <!--banner轮播-->
  <div class="swiper-container" ref="Swiper">
    <!-- 遍历banner数据生成图片 -->
    <div class="swiper-wrapper">
      <div class="swiper-slide" v-for="item in swiperData" :key="item.id">
        <img :src="item.imgUrl" />
      </div>
    </div>
    <!-- 如果需要分页器 -->
    <div class="swiper-pagination"></div>
    <!-- 如果需要导航按钮 -->
    <div class="swiper-button-prev"></div>
    <div class="swiper-button-next"></div>
  </div>
</template>

<script>
import Swiper from "swiper";
import "swiper/css/swiper.min.css";
export default {
    name: "Swiper",
    //接受List组件或Floor组件传递的不同的轮播图数据
    props: ["swiperData"],

    watch:{
    //监听bannerList改变 准备实例化swiper
    swiperData:{
      //Floor传递过来的数据不会改变,开启第一次监听
      immediate: true,
      handler(){

        //如果数据还没来是空数组就不绑定Swiper
        if(!this.swiperData.length) return

        //因为实例化swiper是操作新Dom handler是监听数据改变就执行但是Dom还没更新
        //写在$nextTick中就是在Dom更新之后执行了
        this.$nextTick(() => {
          
          new Swiper(this.$refs.Swiper , {
            direction: "horizontal", // 垂直切换选项
            loop: true, // 循环模式选项

            // 如果需要分页器
            pagination: {
              el: ".swiper-pagination",
            },

            // 如果需要前进后退按钮
            navigation: {
              nextEl: ".swiper-button-next",
              prevEl: ".swiper-button-prev",
            },
          });
        })
      }
    }
  }

};
</script>

<style>
</style>